The present invention relates to marine skimmer craft that is to say watercraft of the kind that is only partially immersed and skims along the surface of the water when propelled, being supported at least partly by aerodynamic force produced by suitable support means.
One object of the invention is to provide marine craft with support means whose configuration may be altered, and to allow such craft to be propelled by means of an air-screw so that they will be particularly stable when skimming and will travel at high speed through air and water.
Air-cushion vehicles in which force-fed air flows under the vehicle are already being used at sea, but the ground effect which they employ allows them to skim at only a limited height.
An aircraft-like ram-winged boat is also known, which has two heavily cambered, large span wings which generate lift in the slip-stream.
The use of air-cushion vehicles at sea is restricted by sea conditions which, if too rough, cause the propulsion system to make too much noise and to operate inefficiently. In the case of the ram-winged boat the large span of the wings is a hindrance when it moves about in port.
Another object of the invention is to provide a marine craft with support means whose configuration can be altered, which can move through air and water, and which is particularly stable in the skimming state.